Products comprising corn oil and corn meal obtained from corn

ABSTRACT

Methods of manufacturing and processing corn oil and corn meal obtained from whole corn are included in useful products. The corn oil is extracted from the whole corn to form the corn meal. The corn oil generally comprises levels of nutrients not found in commercially available corn oils, since most or all of the corn grain, rather than just the germ, is exposed to the extraction process. The corn grain generally includes the steps of flaking corn grain having a total oil content of from about 3% to about 6% and extracting a corn oil from the flaked corn grain.

The present application is a continuation-in-part of copending U.S.patent application Ser. No. 09/927,836, filed Aug. 10, 2001, which was acontinuation-in-part of copending U.S. patent application Ser. No.09/637,843, filed Aug. 10, 2000, which was a continuation-in-part ofapplication Ser. No. 09/249,280, filed Feb. 11, 1999 now U.S. Pat. No.6,313,328, the entire disclosures of which are hereby incorporated byreference.

FIELD OF THE INVENTION

The present invention relates to methods of forming products derivedfrom oil and meal extracted from corn which preferably has an oilcontent of about 3% by weight to about 6% by weight.

BACKGROUND OF THE INVENTION

Corn, Zea mays L., is grown for many reasons including its use in foodand industrial applications. Corn oil and corn meal are two of manyuseful products derived from corn.

Commercial processing plants utilizing conventional methods forextracting corn oil from conventional corn separate the corn seed intoits component parts, e.g., endosperm, germ, tipcap, and pericarp, andthen extract corn oil from the corn germ fraction. Corn germ produced bywet or dry milling is processed either by pressing the germ to removethe oil or by flaking the germ and extracting the oil with a solvent. Inboth processes, because the germ was separated from the remainder of thekernel, many or all of the valuable components of the endosperm fractionare absent from the oil.

During dry milling, the corn kernel after removal of the germ is groundinto flour (i.e., “meal”) and processed without separating the remainingvarious components of the grain. The milled products, i.e. grits, mealand flour, are then subjected to heat treatments during processing.

In the wet milling process, corn is placed in large steep tanks to besoaked for 2 to 3 days in a mixture of warm water and sulfur dioxide ordilute sulfuric acid. The steeping facilitates the separation of thegrain into its component parts (i.e., germ, fiber, starch and gluten(protein)). The germ is then separated out. Similarly, fibrous materialsmay be screened off and the starch and protein are separated usingdensity differences. Often, further milling is needed to separate outthe starch and protein.

A corn-based feed product known as hominy feed is obtained from the drymilling process and is a mixture of corn bran, corn germ, and endosperm,and has a minimum of about 4% by weight oil. Several steps includingcracking, grinding, sieving, and blending are required to manufacturehominy feed and the resulting particle size of hominy feed is smallrelative to meal made by the extraction method described herein.

Industry and health advocates are continually in search of morenutritious products derived from corn. Thus, there exists a need forimproved products derived from corn oil and corn meal.

BRIEF SUMMARY OF THE INVENTION

Finished products containing corn oil and/or corn meal obtained fromconventional corn include, for example, cooking oil, animal feed,aquaculture feed, paper and paper products, numerous food products suchas salad dressings, extruded and/or puffed snack foods, productscontaining corn sweeteners, cereals, chips, puddings, candies, andbreads.

One aspect of the invention provides a nutritious animal feed comprisingthe corn meal remaining after extraction of oil from corn. Such corntypically has oil content of from about 3% by weight to about 6% byweight. The animal feed can comprise other nutritious products such asvitamins, minerals, seed-derived meal, meat and bone meal, salt, aminoacids, feather meal, and many others used in the art of feedsupplementation. Further, meal prepared using whole corn may be blendedwith the meal of the present invention. The animal feed composition canbe tailored for particular uses such as for poultry feed, swine feed,ruminant feed such as cattle feed, equine feed, aquaculture feed, petfood and can be tailored to animal growth phases. Particular embodimentsof the animal feed include growing broiler feed, swine finishing feed,cattle feed, and poultry layer finishing feed. Feed products can be madewith the extracted corn meal that will have a higher relative percentageof protein and lower relative percentage of oil than similar productsproduced having conventional corn milling procedures.

In another embodiment, the method of processing corn includes anextracting step wherein flaked corn grain is pressed to extract an oil.Alternatively, the flaked corn grain is subject to solvent-based oilextraction. Solvents used to extract miscible or soluble substances fromthe flaked grain included one or more of the following: any of thehexanes, isoproplyl alcohol, supercritical CO₂ and ethyl alcohol.Extracting steps can produce a miscella and a corn meal.

In one preferred embodiment, the whole corn grain to be processed intooil and meal has an oil content of from about 3% by weight to about 6%by weight. Preferably, this corn grain has a fiber content of about 2%,a starch content of about 65%, and a total protein content of at leastabout 7% by weight, at least about 9% by weight, at least about 11% byweight, or from about 7% by weight to about 20% by weight. Also,preferably, the whole corn grain has a total lysine content of at leastabout 0.15% by weight, at least about 0.5% by weight, or from about0.15% by weight to about 2.0% by weight. The whole corn grain to beprocessed also preferably has a total tryptophan content of at leastabout 0.03% by weight, at least about 0.20% by weight, or from about0.03% by weight to about 2.0% by weight. In producing the desired meal,the whole corn grain can either be cracked and then flaked or may beflaked without cracking.

Preferably, the flaked or cracked and flaked corn is subjected to an oilextraction process such as solvent extraction, hydraulic pressing,expeller pressing or aqueous and enzyme extraction. Following oilextraction, a corn meal is preferably produced which has a fiber contentof about 3% by weight, a starch content of about 65% by weight, and aprotein content of about 9% by weight, at a moisture content of about12% by weight. The resultant meal also preferably has a meal fat contentof from about 0.2% by weight to about 2.0% by weight.

Another aspect of the invention provides a method of using extractedcorn meal in an animal feed ration comprising the step of: 1) providingan extracted corn meal prepared by at least flaking whole corn andextracting the flaked corn to remove a portion of the corn oiltherefrom; and 2) including the extracted corn meal in an animal feedration.

Yet another aspect of the invention provides a method of using anextracted corn oil in a food product comprising the steps of: 1)providing an extracted corn oil obtained by at least flaking whole cornto form flaked corn and extracting the flaked corn to remove a portionof the corn oil therefrom and form the extracted corn oil; and 2)including the extracted corn oil in a food product.

Still another aspect of the invention provides a method of usingextracted corn oil as a feedstock in an oil refining process. The methodcomprises the steps of: 1) providing an extracted crude corn oilobtained by at least flaking whole corn to form flaked corn andextracting the flaked corn to remove a portion of the corn oil therefromand form the extracted crude corn oil; and 2) including the extractedcrude corn oil in a raw material stream of an oil refining process.

The miscella remaining after extraction is preferably desolventized toproduce a corn oil. The corn oil preferably has a phosphorus content ofless than about 800 parts per million, a free fatty acid content of lessthan about 0.5% by weight and/or a neutral oil loss of less than about3% by weight.

A preferred embodiment also provides a method of obtaining corn oil andsolvent extracted corn meal from corn. Preferably, the corn has an oilcontent of from about 3% by weight to about 6% by weight. The methodprovides steps of: 1) tempering the corn; 2) cracking the tempered corn;3) conditioning the cracked corn; 4) flaking the cracked and conditionedcorn; 5) extracting the flaked corn; and 6) removing the solvent fromboth the corn oil and solvent extracted corn meal. The method provides agreater overall content of corn oil and concentrates the proteins in themeal. Moreover, solvent extractable pigments are removed from thesolvent extracted corn meal.

Another aspect of the invention provides a corn oil-based productcomprising corn oil obtained by extraction of whole corn or at least theendosperm and germ of corn. Preferably, the whole corn has an oilcontent of from about 3% by weight to about 6% by weight. The cornoil-based product can comprise other components such as vinegar, spices,vitamins, salt, hydrogen (for forming hydrogenated products), and water.The corn oil used in the products of the invention will generallycontain a higher proportion of β-carotene, xanthophylls or tocotrienolthan similar products made with corn oil obtained from corn employingconventional wet or dry milling methods. The corn oil, used in theproducts of the invention, is generally produced by exposing the entirecorn grain, the cracked corn grain or the flaked corn grain toextraction without separation of the germ from the endosperm. Therefore,the solvent-extractable nutrients present in the endosperm are extractedinto the corn oil that has been extracted from the germ and endosperm.Products that can be made with the oil prepared as described hereininclude, but are not limited to, salad dressings, cooking oils,margarines, spray-coated food or feed products, breads, crackers, snackfoods, lubricants, and fuels.

In another embodiment of the present invention, whole corn, preferablyhaving an oil content of from about 3% by weight to about 6% by weight,is process by steps including cracking, conditioning, flaking andextraction with a solvent. Preferably, oil is also extracted bysubjecting the flaked corn grain to a solvent-based extraction process,hydraulic pressing and/or expeller pressing or aqueous and/or enzymeextraction processes. Solvents used to extract miscible or solublesubstances from the flaked grain include all forms of commerciallyavailable hexanes, isopropyl alcohol, ethanol, supercritical carbondioxide or mixtures thereof. Preferably the corn oil miscella is refinedby additional processing.

Another aspect of the invention provides various methods of formingextracted blended meals. A first embodiment of this aspect of theinvention provides a method of forming an extracted blended mealcomprising an extracted meal obtained from corn and one or more otheroilseed meals such as soy, sunflower, canola, or cottenseed, the methodcomprising the step of: 1) combining corn grain and one or more otheroilseed grains to form a grain mixture; and 2) subjecting the grainmixture to flaking and an extraction process to remove oil therefrom andform the extracted blended meal.

A further blended meal embodiment provides a method comprising the stepsof: 1) combining a cracked and conditioned corn with another cracked andconditioned oilseed to form a conditioned mixture; 2) flaking theconditioned mixture to form a flaked mixture; and 3) subjecting theflaked mixture to an extraction process to remove oil therefrom and formthe extracted blended meal.

A still further blended meal embodiment provides a method comprising thesteps of: 1) combining a cracked, conditioned and flaked corn with acracked, conditioned and flaked other oilseed to form a flaked mixture;and 2) subjecting the flaked mixture to an extraction process to removeoil therefrom and form the extracted blended meal.

In another blended meal extracted corn meal is combined with one or moreextracted other oilseed meals to form a blended meal, wherein theextracted corn meal has been obtained by at least flaking and extractingcorn to form the extracted corn meal.

In each method, where appropriate, an optional drying step may beintroduced to reduce the barrier that arises when water present ineither the cracked or flaked corn impedes solvent extraction bywater-immiscible solvents.

Another aspect of the invention provides the use of a corn meal in ananimal feed or human food, wherein the corn meal is obtained afterextraction of corn oil from whole kernels of corn having an oil contentof from about 3% by weight to about 6% by weight.

Yet another aspect of the invention provides the use of a corn oil in ananimal feed or human food, wherein the corn oil is obtained byextraction from whole kernels of corn having an oil content of fromabout 3% by weight to about 6% by weight.

Still another aspect of the invention provides a method of usingextracted corn oil as an ingredient in cosmetic applications. The methodcomprises the steps of: 1) providing an extracted crude corn oilobtained by at least flaking whole corn to form flaked corn andextracting the flaked corn to remove a portion of the corn oil therefromand form the extracted crude corn oil; and 2) including the extractedcrude corn oil in a cosmetic product. These types of cosmetics includebut are not limited to lipstick and eyeliner.

Other aspects of the invention provide corn oil-containing and/or cornmeal-containing products made by the processes described herein.

Unless otherwise defined, all technical and scientific terms andabbreviations used herein have the same meaning as commonly understoodby one of ordinary skill in the art to which this invention pertains.Although methods and materials similar or equivalent to those describedherein can be used in the practice of the present invention, suitablemethods and materials are described below without intending that anysuch methods and materials limit the invention described herein. Allpatents publications and official analytical methods referred to hereinare incorporated by reference in their entirety. Additional features andadvantages of the invention will be apparent from the followingdescription of illustrative embodiments of the invention and from theclaims.

DETAILED DESCRIPTION OF THE INVENTION

Corn oil can be rapidly and efficiently extracted on a commercial-scalefrom corn grain by optionally cracking and then conditioning, andflaking the corn grain and extracting a corn oil. In one preferredembodiment, corn grain useful in the oil processing method of theinvention has a total oil content of from about 3% by weight to about 6%by weight. Suitable flaking equipment and methods include conventionalflaking equipment and methods used for flaking soybean and other similaroilseed types. Suitable extracting equipment and methods may includeconventional methods used for extracting oil from soybean flakes andother similar oilseed types.

Corn harvested from any of several different types of corn plants isuseful in the invention. These types of corn plants are, for example,hybrids, inbreds, transgenic plants, genetically modified plants or aspecific population of plants. Enhanced extracted meals can be made bysubjecting corn to the extraction process described herein. Useful corngrain types include, for example, flint corn, popcorn, flour corn, dentcorn, white corn, and sweet corn that are amenable to flaking.

As used herein, the terms “whole kernel” or “whole corn” mean a kernelthat has not been separated into its constituent parts, e.g. the hull,endosperm, tipcap, pericarp, and germ have not been purposefullyseparated from each other. The whole corn may or may not have beenground, crushed, cracked, flaked, or abraded. Purposeful separation ofone corn constituent from another does not include random separationthat may occur during storage, handling, transport, crushing, flaking,cracking, grinding or abrading. A purposeful separation of theconstituent part is one wherein at least 50% of one constituent, e.g.,germ, has been separated from the remaining constituents.

Suitable corns used as a raw material for preparing the corn oil andcorn meal used in the invention have the general nutrient profiles asshown in Table 1. Amounts are expressed on an “as is” or “as fed”moisture level. Protein, oil, and starch levels can vary in a number ofpossible combinations in the whole corn used as a raw material for mealand oil of the invention. Acceptable amounts of moisture, oil, proteinand starch are illustrated in Table 1.

TABLE 1 Amount Sample 1 General Amount Component (weight %) (weight %)Moisture 14  5-25 Oil 3.6  3-6 Protein 7.8  5-10 Starch 72.6  50-80Lysine 0.26 0.15-2.0 Tryptophan 0.082 0.03-2.0

Other suitable properties for preferred corn suitable as a raw materialare set forth in Table 2. The amounts listed in Table 2 are expressed onan “as is” or “as fed” moisture level. The amounts shown in Table 2 areexemplary for a corn grain having 3% by weight to 6% by weight oil and7.5% by weight protein.

TABLE 2 Component General Amount (weight %) Ash 0.1-4.0 Lysine 0.15-1.0 Tryptophan 0.03-1.0  Methionine 0.13-1.0  Total Sulfur Amino Acids0.23-1.85 Valine 0.2-1.8 Isoleucine 0.08-1.36 Arginine 0.11-1.88Threonine 0.08-1.3  Leucine 0.52-4.12 Histidine 0.07-1.08 Phenylalanine0.22-1.76 Alanine 0.17-2.80 Aspartic 0.37-2.96 Cystine 0.11-0.88Glutamic 0.47-7.6  Glycine 0.11-1.84 Proline 0.21-3.44 Tyrosine0.02-0.54 Serine  0.1-1.81

The yellow #2 corn is generally subjected to an extraction process asdescribed herein to provide the corn oil and corn meal to be included inthe finished products of the invention. The “finished product” may bethe resulting oil or meal itself or it may refer to a product made bycombining the corn oil and/or corn meal of the invention with a varietyof other ingredients. The specific ingredients included in a productwill be determined according to the ultimate use of the product.Exemplary end uses of the finished products include feed includinganimal feed, raw material for chemical modification, biodegradablematerial, blended food product, edible oil, cooking oil, lubricant,biodiesel, snack food, cosmetics, and fermentation process raw material.Products incorporating the meal described herein also include completeor partially complete swine, poultry, and cattle (or other ruminant)feeds, pet foods, and human food products such as extruded snack foods,breads, as a food binding agent, aquaculture feeds, fermentablemixtures, food supplements, sport drinks, nutritional food bars,multi-vitamin supplements, diet drinks, and cereal foods. Productsincorporating the starch described include, e.g., cardboard, paperproducts and industrial materials.

Important to note is that starting with a single corn type (e.g., 4% byweight oil and 7.5% by weight protein), more than one corn meal type maybe produced depending on the end product nutritional requirements by theprocess of the invention. The significance of this flexibility relatesto the nutrient density within feed products and to dietary requirementsof animals. One significant advantage of the use of the extractionprocess for processing corn is that an extracted corn meal can be madeto have a specific oil level depending on the extent of oil extraction.Once the oil is removed from the flakes, the remaining corn meal has anutrient density for protein, amino acids, and other nutrients notremoved by the process, greater or different than normal corn grain andgreater than that of the starting corn, e.g., greater than 7.5% byweight protein.

According to one extraction process used in preparing the corn oil andcorn meal as described herein, whole grain corn, preferably containingfrom about 3% by weight to about 6% by weight oil, is optionallytempered, optionally cracked, and then conditioned and flaked. Afterflaking, the flaked corn is extracted as described herein.

The moisture content of the grain can affect the flaking process. It maybe necessary for the moisture of the corn grain to be increased by about1% to about 15% before flaking the seed. Optimizing the grain moisturecontent to facilitate efficient processing is within the knowledge ofthose of ordinary skill in the art.

The grain corn is optionally tempered before the conditioning andextracting process. As used herein, the term “tempering” is usedinterchangeably with the terms “heat soaking” or “steaming” and is astep undertaken to uniformly distribute moisture through the entire cornkernel. Any tempering method known in the art is acceptable. In general,the corn is steeped in an appropriate amount of water for any suitablelength of time, such as at least 20 minutes, preferably at least 4 hoursmore, more preferably at least 6 hours, even more preferably at least 12hours, or most preferably at least 24 hours. After the corn has steepedfor the desired length of time, its moisture content is retested. Thecorn may be stored for short periods of time, but is preferablyprocessed within 24 hours of tempering and most preferably processedimmediately.

Whole grain corn is also optionally cracked. In a preferred embodiment,the whole corn is cracked after tempering yet before conditioning. Thecorn may be cracked by passing the whole grain corn between two rollerswith corrugated teeth spinning toward each other spaced by a definedgap, and/or passing through a grind mill where a rotating toothed diskspins at an adjustable distance from a stationary disk, and/or the useof a hammermill where two rotating metal “hammer” like devices spinningnext to one another. Methods for cracking corn or seeds are described inWatson, S. A. & P. E. Ramstad, ed. (1987, Corn: Chemistry andTechnology, Chapter 11, American Association of Cereal Chemist, Inc.,St. Paul, Minn.), the disclosure of which is hereby incorporated byreference in its entirety. A “cracked” corn is a corn that has undergonethe above-described cracking process.

Regardless of whether cracking occurs, the corn is conditioned usingmethods known to those of ordinary skill in the art and/or methodsdescribed herein. As used herein, the term “conditioning” refers to aprocess by which the corn kernel is softened or plasticized to render itmore pliable and amenable to the flaking and extraction processes.Conditioning may include the addition of steam (saturated and/ornon-saturated steam) and/or water to the corn. This is done by, forexample, the use of a steam jacketed screw conveyor.

The corn grain is then flaked to any appropriate useful size. As usedherein, the term “flaking” refers to a process by which corn grain ispassed one or more times through flaking rollers to produce flakes. Theflaked corn may have a final flake thickness of about 0.01 inches toabout 0.03 inches (˜0.25 mm to 0.75 mm) or preferably about 0.02 inches(0.50 mm), although other thicknesses may also be used. Useful flakethickness may depend on external limiting parameters such as the oilcontent of the corn, the moisture content, the corn type, e.g., dent orflint, and the oil extractor type. Suitable methods for flaking wholecorn are detailed herein and in D. R. Erickson, Practical Handbook ofSoybean Processing Utilization (1995, AOCS Press), the entire disclosureof which is hereby incorporated by reference. Suitable flaking methodsalso include those known to those of ordinary skill in the art ofoilseed processing.

After the corn is tempered, cracked and/or conditioned and flaked, theflaked corn is subjected to an extraction process to extract oil to forman extracted corn meal (ECM). Corn oil is extracted from flaked grain byone or more extraction steps using any extraction method. Generally,substantially all of the oil is extracted in a single extractionprocess. Useful extraction methods include solvent extraction,continuous solvent extraction, hydraulic pressing, expeller pressing,aqueous and/or enzyme extraction. Useful solvents for solvent extractioninclude, for example, all forms of commercially available pentane,hexanes, isopropyl alcohol, ethanol, supercritical carbon dioxide,combinations thereof, and other similar solvents. For example, corn oilcan be extracted from flaked corn using a hexane-based solventextractor. Solvent extractors can include both percolation and immersiontype extractors. In a preferred embodiment, a continuous solventextraction process allows the flaked corn to remain in contact with thesolvent for at least 10 minutes, preferably at least 30 minutes, morepreferably at least 60 minutes, and most preferably at least 90 minutes.

Materials removed from solvent-based extractors include wet flakes andmiscella. A miscella is a mixture of extracted oil and solvent. The wetflakes are the materials that remain after some or all of thesolvent-soluble material has been extracted. Wet flakes also contain aquantity of solvent. Solvent is reclaimed from both the miscella and wetflakes using methods such as rising film evaporation, or drying, andraising the temperature using equipment such as flash tanks and/orde-solventiser/toasters. For example, heat is applied to the wet flakesor miscella under atmospheric pressure, under elevated pressure, orunder vacuum to evaporate the solvent. The evaporated solvent is thencondensed in a separate recovery system, and optionally dewatered andrecycled to the extractor.

Desolventized miscella is commonly termed crude oil, which can be storedand/or undergo further processing. Crude oil can be refined to produce afinal oil product. Methods for refining crude oil to obtain a final oilproduct are known to those of ordinary skill in the art. Hui (1996)provides a thorough review of oils and oilseeds (Bailey's Industrial Oiland Fat Products, Fifth Ed., Vol. 2, Wiley and Sons, Inc., New York).Chapter three of Hui (pp. 125-158), the disclosure of which is herebyincorporated by reference, specifically describes corn oil compositionand processing methods. Crude oil isolated using the flaking methodsdescribed herein is of a high quality but can be further purified asneeded using conventional oil refining methods.

In one embodiment, the present invention relates to a method ofrecovering lighter particles, such as fines, during the processing ofcorn. As used herein, the term “fines” means any particle of the cornprocess that passes through a #18 sieve having a 1.00 mm opening asdefined in ASTM E-11 specifications. The recovery of the particles mayoccur before, after, or during any step in the process, such as duringthe moisture removal step, during the cracking step or before or afterthe flaking process. In general, fines are recovered by passing acurrent of gas (e.g., air, nitrogen, argon) over the corn at a suitablevelocity and direction such that smaller and lighter particles arecarried away in the stream, leaving behind larger, heavier particles.Alternatively, lighter particles can be separated from heavier particlesusing a liquid (e.g., water, oil, process water) spray. The liquid isapplied broadly enough to physically eliminate the lighter, airborneparticles. The liquid spray can include components that add value to theend product, such as vitamins, minerals, enzymes, and combinationsthereof. In addition, the liquid spray can further comprise a causticliquid. Regardless of the separation method, these fine particles can becaptured or recovered by any method known in the art such as using abaghouse. Preferably, the recovered lighter particles can bereintroduced into starch-containing product streams for the recovery ofstarch. Additionally the fines may be sold as an animal feed.

Corn endosperm includes some valuable components such as carotenoids,lutein, and zeazanthin. Carotenoids in grains are classified into twogeneral groups, the carotenes and the xanthophylls. The carotenes areimportant because they are vitamin A precursors. Blessin et al. (CerealChemistry, 40, 582-586 (1963)) found that over 90% of the carotenoids,of which beta-carotene is predominant, are located in the endosperm ofyellow #2 corn and less than 5% are located in the germ. Vitamin A isderived primarily from beta-carotene.

Another group of valuable components found in the endosperm includes thetocotrienols. Grams et al. (1970) discovered that in corn, tocotrienolswere found only in the endosperm, whereas the germ contained most of thetocopherols. Tocotrienols can be extracted from plant material usingvarious solvents. Processes for recovering tocotrienols from plantmaterial are described by Lane et al. in U.S. Pat. No. 5,908,940, theentire disclosure of which is incorporated by reference.

Corn oil or corn meal quality is determined by evaluating one or morequality parameters such as the oil yield, phosphorus content, free fattyacid percentage, the neutral starch percentage, protein content, andmoisture content. Any known method can be used to calculate one or moreof the quality parameters for evaluating the oil or meal quality.

Table 3 displays component amounts for commercially available crude oiland solvent extracted yellow #2 corn oil. The extracted oil obtainedfrom solvent extracted yellow #2 corn has greater amounts of zeazanthinand beta-carotene than does commercially available crude oil obtainedfrom wet or dry milling methods. Conventional crude oil can be obtainedfrom suppliers such as Cargill, Incorporated (Minneapolis, Minn.).

TABLE 3 Commercially Solvent Extracted Component Available Crude OilYellow #2 Corn Oil Lovibond (Yellow, Red) —, 14 70, 12 Free Fatty Acid3.0 2.42 Zeazanthin (mg/g) 0.005 5.0 Beta-Carotene (IU/100 g) 15.5 727Vitamin A(IU/100 g) 100 <100 Vitamin B₆ (mg/100 g) 0.400 — Vitamin B₁₂(mg/100 g) 0.500 — Niacin (mg/100 g) 2.05 — α- tocopherol (PPM) 11.88184 β- tocopherol (PPM) <0.5 <0.5 γ- tocopherol (PPM) 29.94 311 δ-tocopherol (PPM) 27.4 43 α- tocotrienol (PPM) — 231 β- tocotrienol (PPM)— 23 γ- tocotrienol (PPM) — 1463 δ- tocotrienol (PPM) — 63 C16-palmitic10.7 10.7 C18-stearate 1.9 1.9 C18:1-9c-oleic 27.5 25.5 C18:2-9c,12c-linoleic 57.1 58.4 C18:3-9c, 12c, 15c- 1.09 1.2 linolenicPhosphorous (PPM) 520 — Folic Acid (mg/100 g) 25.0 — Pantothenic Acid0.250 — (mg/100 g) Monoglycerides — 0.03 Diglycerides — 1.62Triglycerides — 91.36 Hydrocarbons — 0.02 Squalane — <0.01 Squalene —0.08 Steryl Esters — 0.91 Stanol Esters — 0.3

Oil-based products made with corn oil obtained by the extraction methoddescribed herein can contain higher levels of other important nutrientsthan similar products made with corn oil produced by conventional wetand dry milling processes. The corn oil obtained by the extractionmethods described herein will include the corn oil from the germ andendosperm, as well as other components extracted from the whole corn.The other extracted components include such other desirable nutrientsas, tocotrienols, tocopherols, carotenoids, carotenes, xanthophylls, andsterols.

Tocopherols (vitamin E) and vitamin A are antioxidants and fat-solublevitamins. When included in the diet, both have demonstrated healthbenefits. Blending of oil of the present invention with other oils orsubstances to achieve an appropriate level of beta-carotene, vitamin E,and tocotrienols is deemed within the scope of the present invention. Insome embodiments, extracted corn oil prepared as described hereincomprises from about 50 parts per million (ppm) to about 300 ppm ofα-tocopherol and from about 1000 ppm to about 3000 ppm of γ-tocotrienol.

Oil produced in accordance with the present invention also may includeapproximately a 10-fold to a 17-fold increase in tocotrienol contentover wet or dry milled crude corn oil. Using the method of optionallytempering, cracking, and/or optionally conditioning, and flaking, thecorn oil was extracted and was then analyzed for tocotrienol content.The actual minimum and maximum values for tocotrienol content willdepend upon the particular corn used.

The oxidative stability index (OSI), measured in hours, is a measure ofan oil's relative stability toward oxidation. Generally, the greater theOSI, the less susceptible the oil is toward oxidation and the longer ittakes to oxidize the oil under test or use conditions. In addition, thegreater that the content of unsaturated fatty acids is present in theoil, the lower the OSI. Exemplary oils prepared according to theextraction method described herein generally possess OSI values rangingfrom about 10 hours to about 22 hours.

Extraction of carotenes and xanthophylls and other pigments is describedin detail by Blessin (Cereal Chemistry, 39, 236-242 (1962); the entiredisclosure of which is incorporated by reference). Combinations ofsolvents, primarily ethanol and hexanes, can be used to extractcarotenes and xanthophylls from corn. Ethanol, hexanes, other solventscombinations, and ratios thereof may be used to produce oil of thepresent invention on a commercial scale.

Exemplary embodiments of the crude oil obtained according to theextraction method described herein generally possess the partialcomposition profile featured in Table 4.

TABLE 4 Extracted Whole Extracted Whole Corn (Example) Corn (Range)Component (Weight %) (Weight %) Free Fatty Acids (FFA) 2.42  0.7-3.00C16:0 10.7  9-14 C18:0 1.9 1.5-3.5 C18:1,cis 25.5 20-40 C18:2, cis 58.445-65 C18:3 1.2 0.6-2.0 Total Tocopherols (ppm) 1780 1000-3000

Fatty acids generally found in the corn oil generally include palmitic,stearic, oleic, linoleic and linolenic acids.

The crude oil prepared according to the methods described herein can besubsequently partially or completely hydrogenated. Suitable methods forpartially or completely hydrogenating oil are described in D. R.Erickson, Practical Handbook of Soybean Processing Utilization (1995,AOCS Press), the entire disclosure of which is hereby incorporated byreference.

When making oil-based products according to the invention, thoseproducts can include conventional corn oil, soy oil, canola oil, oliveoil, palm oil, sunflower oil, safflower oil, antioxidant, flavoring,hydrogenated oil, partially hydrogenated oil and/or animal fat. Bymixing the corn oil herein with one or more other oils, blended oilproducts are made. The corn oil-based products can also includematerials such as food additives, salt, fat, food colors, β-carotene,annatto extract, curcumin or tumeric, β-apo-8′-carotenal and methyl andethyl esters thereof, natural or synthetic flavors, antioxidants, propylgallate, butylated hydroxytoluene, butylated hydroxyanisole, natural orsynthetic tocopherols, ascorbyl palmitate, ascorbyl stearate, dilaurylthiodiproprionate, antioxidant synergists, citric acid, sodium citrate,isopropyl citrate, phosphoric acid, monoglyceride citrate, anti-foamingagent, dimethyl polysiloxane, crystallization inhibitor, oxystearin,amino acids, vitamin, minerals, carbohydrates, sugars, herbs, spices,acidity regulators, firming agents, enzyme preparations, flour treatmentagents, viscosity control agents, enzymes, lipids, and/or vegetable oranimal protein. Additionally, these edible products can be enhanced orenriched with protein supplements containing utilizable protein. Anexemplary food product such as a breakfast cereal could includeingredients such as meal of the invention, wheat and oat flour, sugar,salt, corn syrup, milled corn, dried fruit, vitamin C, B vitamins, folicacid, baking soda, and flavorings.

Other exemplary oil-based products that can comprise the oil preparedherein include food oil, cooking oil, edible oil and blended oil.

Equipment used for the extraction of oil from oilseeds, such as soybeanand canola, can be used to prepare the corn oil and extracted corn mealdescribed herein. Useful commercial-scale oilseed flakers can beobtained from French Oil Mill Machinery Company, Piqua, Ohio; RoskampChampion, Waterloo, Iowa; Buhler, based in Switzerland with offices inPlymouth, Minn.; Bauermeister, Inc., Germany; Consolidated ProcessMachinery Roskamp Company, on the world wide web athttp://www.cpmroskamp.com, and Crown Iron Works, Minneapolis, Minn.

Commercial-scale methods and equipment are sufficient for extractingcorn oil from at least about 1 ton of corn per day. In some embodiments,the capacity of commercial-scale operations ranges from about 100 tonsof corn per day to about 3000 tons of corn per day, or the capacityranges from about 700 tons of corn per day to about 1700 tons of cornper day. Commercial-scale operations that process greater than about3000 tons of corn per day are also sufficient.

The phosphorus concentration of crude oil can be determined using AOCSmethod Ca 12-55. AOCS method Ca 12-55 identifies the phosphorus or theequivalent phosphatide zinc oxide, followed by the spectrophotometricmeasurement of phosphorus as a blue phosphomolybdic acid complex. AOCSmethod Ca 12-55 is applicable to crude, degummed, and refined vegetableoils. The phosphorus concentration is converted to phospholipidconcentration, i.e., gum concentration, by multiplying the phosphorusconcentration by 30. In some embodiments, corn oil produced according tothe invention includes about 100-400 ppm of phosphorus.

The free fatty acid percentage of oil can be determined using AOCSmethod Ca 5a-40. AOCS method Ca 5a-40 identifies the free fatty acidsexisting in the oils sample. AOCS method Ca 5a-40 is applicable to allcrude and refined vegetable oils, marine oils, and animal fats. Theneutral oil loss during processing is determined by adding the gumpercentage and the free fatty acid percentage together. The amount offree fatty acid obtained in the extracted corn oil will depend upon theamount of fatty acids found within the whole corn from which the oil wasextracted. In some embodiments, the free fatty acid content of theextracted oil ranges from about 0.70% to about 3.00 weight %.

Oil color can be determined using AOCS method Cc 13b-45. AOCS method Cc13b-45 identifies the color of an oil sample by comparing the oil samplewith known color characteristics. AOCS method Cc 13b-45 is applicable tofats and oils provided no turbidity is present in the sample. Colorvalues are evaluated qualitatively by visual inspection of the oil.Generally, visual inspection results in an oil being classified as alight oil or a dark oil compared to a known oil color. Color values arequantitated by determining a red color value and a yellow color valueusing the AOCS method Cc 13b-45. Typically, crude corn oil isolatedusing conventional dry milling methods has a red color value rangingfrom about 7 to about 10 and a yellow color value ranging from about 60to about 70. It is expected that corn oils isolated using crackingmethods described herein will have oil colors that qualitatively areconsidered light and generally are lighter than crude corn oil derivedfrom wet or dry milling techniques. The yellow color values may rangefrom about 60 to about 70 and red color values may range from about 7 toabout 10, as determined by AOCS Method Cc 13b-45.

The extracted corn oil can be used as a raw material for chemicalmodification, a component of biodegradable material, a component of ablended food product, a component of an edible oil or cooking oil,lubricant or a component thereof, biodiesel or a component thereof, acomponent of a snack food, and a component of cosmetics. Since the oilobtained by the extraction process herein has one or more componentsobtained from non-germ parts of the corn kernel, the oil is enhanced.When making blended oils with the extracted oil, the blending can bedone before, during or after the extraction process.

Biodiesel can be produced using the extracted corn oil of the invention.Biodiesel is a general term used for a variety of ester-based oxygenatedfuels. Biodiesel produced today is a mixture of fatty acid methyl estersproduced by methylating refined vegetable oil. Refined oil is preferableto crude oil or spent fryer oil due primarily to the quality of theglycerol by-product. The main drawbacks with previous biodiesel productsand related vegetable oil lubricants are low temperature properties andreactivity toward oxidation and polymerization. A preferred biodieselproduct comprises a low cloud point, reduced stearic and polyunsaturatedfatty acid content, and high oleic acid content. Pour point correlateswith low temperature properties and is influenced by the saturated fattyacid content of the oil. Polyunsaturated fatty acids are moresusceptible to oxidation and polymerization reactions.

Solvent extracted corn oil corn can be further processed to formlubricants such as by published procedures practiced currently in theindustry (see, e.g., U.S. Pat. No. 6,174,501). Meal produced from theflaking and oil extraction process described herein is used to produceunique feed products such as poultry feed, swine feed and ruminant feed.The corn meal used herein has been obtained after extraction of oil fromwhole kernels of corn, wherein the kernel has not been separated intoits constituent part, although the kernel may or may not have beenground, flaked, cracked, chipped, or abraded. The process of removingthe oil from corn via extraction serves to concentrate the remainingnutrients such as protein and essential amino acids.

The meal remaining after the oil is removed from the flaked corn byextraction also has significantly improved properties over those ofmeals produced by wet or dry milling processes. Feed products containingpredominantly corn meal produced by extraction require lesssupplementation with protein from other sources such as soybeans thanfeed products containing wet or dry mill processed corn grain. The meal,by virtue of the composition arising from the processing method, offersfeed manufacturers flexibility to produce feeds that could otherwise notbe made. Animal feed rations having unique physical properties such asbulk density, texture, pelletability, and moisture holding capacityand/or unique nutritional properties are created by including theextracted corn meal of the present invention as a component of saidrations. The extracted corn meal isolated using flaking and extractionmethods as described herein can, on its own, be a low-fat corn meal.Alternatively, it can be used in combination with other corn meals ornutritional components to make feed rations and food products. Theextracted corn meal can also be combined with meals made from crops suchas soybeans, canola, sunflower, oilseed rape, cotton, and other crops.The extracted corn meal can also be made from genetically modified cornand/or combined with meals made from transgenic oilseed grains to forman enhanced meal or enhanced product.

The extracted corn meal can be provided as a loose product or a pelletedproduct, optionally in combination with other components. For example, apelleted product could include the extracted corn meal (by itself or incombination with other components) that has been pelleted andsubsequently coated with zein protein. The corn meal can be included inblended meal products that can be provided in loose or pelleted form.

The feed rations prepared with the extracted corn meal will generallymeet the dietary and quality standards set forth in the CODEXALIMENTARIUS or by the National Research Council. The corn meal of theinvention will generally comprise the components in the approximateamounts indicated in Table 5 below.

TABLE 5 Component Weight % Moisture  5-25 Starch 60-80 Protein  7-20 Fat(Oil) 0.1-2.0

When compared to meals made from corn prepared from wet or dry millingprocesses, the extracted corn meal described herein provides a greateramount of key nutional components (nutrients) such as vitamins, folic,pantothenic acid, lysine, tryptophan, and/or niacin.

The extracted corn meal prepared as described advantageously can be madeto contain specific levels of oil and, in particular, specific ratios ofoil to protein, of oil to carbohydrate or of oil to protein tocarbohydrate. For example, normal corn with 8% protein and 4% oil has aprotein:oil ratio of 2.0. Meal produced by extraction to have 10.5%protein and 1.5% oil has a protein:oil ratio of 7.0. This higher rationmakes this meal type and products derived therefrom desirable forcertain applications such as animal feed and protein purification.

Varying levels of nutrients are required by different animals dependingon species, age, and breed. Feed rations comprising different levels ofnutrients are made by subjecting the corn to different degrees ofextraction, i.e., more oil is removed from the corn by subjecting it toextraction to a greater degree. Therefore, feed rations comprising theextracted corn meal of the invention can be made to include differentamounts of fat, protein, and carbohydrates by controlling the extent towhich the corn is extracted. Table 6 details the amounts in which theindicated ingredients are present in animal feed rations comprising theextracted corn meal, the specific inclusion range being indicative ofexemplary rations in which extracted corn meal is a main ingredient andthe general inclusion range being indicative of rations in which one ormore other ingredients, for example, carbohydrate-based energy sourcessuch as sorghum, wheat, and/or other cereal grains or their by-products,or other non-cereal grain ingredients, may be included.

TABLE 6 General Exemplary Ingredient Inclusion Range Inclusion RangeCorn meal described herein 2-95% 50-90% Oilseed Meal¹ 3-35% 10-30% Meatand Bone Meal 0-12% 0-7% Feather Meal 0-6%  0-4% Fat 0-10% 1-6% Salt0.1-0.5%  0.1-0.5% Lysine  0-0.4%   0-0.4% Methionine  0-0.3%   0-0.3%Nutrient Premix 0.01-1.0% 0.01-1.0%  ¹Oilseed meal can consist of, butis not limited to, soy, sunflower, canola, cottonseed, and otherplant-based meals, which themselves may or may not have been subjectedto an oil extraction process.

Meat and bone meal is obtained from suppliers such as DarlingInternational, Inc. (Irving, Tex.). Oilseed meal is obtained fromsuppliers such as Cargill Oilseeds (Cedar Rapids, Iowa). Feather meal isobtained from suppliers such as Agri Trading Corp., (Hutchinson, Minn.).Amino acids are obtained from suppliers such as DuCoa, (Highland, Ill.).

Feed rations are made by mixing various materials such as grains, seedmeals, vitamins, and/or purified amino acids together to form acomposite material that meets dietary requirements for protein, energy,fat, vitamins, minerals, and other nutrients. The mixing process caninclude grinding and blending the components to produce a relativelyhomogeneous mixture of nutrients. Physical properties of the feed rawmaterials and of the compounded feed affect the nutritional quality,storability, and overall value of the products. Suitable processes formanufacturing feed rations are disclosed in Feed ManufacturingTechnology IV (1994, American Feed Industry Association) andincorporated herein in its entirety.

The extracted corn meal may be somewhat analogous to steam-flaked cornin terms of digestibility of the starch fraction, but may have betterdigestibility in ruminants by virtue of the processing conditions. Asdiscussed herein, specific oil levels can be achieved in the extractedmeal by altering processing conditions.

Many types of animal feed rations can be developed using extracted cornmeal of the present type, and for illustration purposes, the followingdiet types will be described herein: meal made from corn grain whereinthe corn grain has an oil content of from about 3% by weight to about 6%by weight and a protein content of about 7.5% by weight, and mealresulting from this corn has an oil content of about 1.5% by weight foruse in a hog finishing diet or in a poultry broiler diet.

Extracted corn meal of the present invention has several advantages overnormal corn grain when used as an ingredient in aquaculture feedproducts. In agriculture, pigments such as carotenoids in feed are oftendeposited in fatty tissue when consumed resulting in an undesirablecolor. For some aquaculture species, consumer preference is for verylight colored tissue. In other species, such as salmon, consumerpreference is for a pink or red tissue. An advantage of extracted cornmeal in aquaculture diets is that some undesired pigments will bereduced by virtue of the process to produce extracted corn meal; thesolvent-soluble pigment compounds (such as carotenoids) are removed fromthe meal and concentrated in the oil. A second advantage of extractedcorn meal over corn dry-milled or wet-milled corn products is theimproved protein content and quality, since the oil has beensubstantially removed from the kernel resulting in a meal product inwhich the protein has been concentrated. Because the meal is obtainedfrom all portions of the kernel, including most or all of the embryo,the proteins are generally of higher quality and quantity than would befound in extracted corn grits. By including extracted corn meal inaquaculture feeds, it will be possible to raise animals with fewerundesirable pigment compounds in the tissue.

Solvent extracted corn meal is also useful for fermentation-basedproduction of compounds, such as, for example, ethanol, lactic acid, andvitamins. A method of producing a fermentation-based product such asethanol comprises combining alpha-amylase enzyme and corn meal thatremains after the extraction of oil from whole corn. This combination isincubated and at least one additive, for example, glucoamylase orprotease, is included to this combination. The combination issubsequently mixed with a micro-organism capable of fermenting a carbonsource to produce the fermentation-based product. Solvent extracted cornmeal from whole corn can be hydrolyzed to provide soluble sugars. Themeal serves as a carbon and nitrogen source for bacterial, fungal, oryeast cultures. Biotin and other vitamins can be produced through thecultivation of microorganisms. Organisms can include Pseudomonasmutabilis (ATCC 31014), Corynebacterium primorioxydans (ATCC 31015),Arthrobacter species, Gibberella species, Penicillium species, orcombinations thereof.

Nutrients used in the cultivation of these and other microorganismsinclude, for example, starch, glucose, alcohols, ketones, and as anitrogen source, peptone, corn steep liquor, soybean powder, ammoniumchloride, ammonium sulfate, ammonium nitrate, extracted corn meal, orurea. Various salts and trace elements may also be included in media forthe culture of microorganisms. The pH of the culture medium is fromabout 4 to about 9, preferably from about 6 to about 8 and mostpreferably about 7 for bacterial species. The pH is preferably fromabout 5 to about 7 for mold or yeast. During cultivation, temperaturesare kept between about 10° C. to about 100° C., preferably between about20° C. to 80° C., more preferably between about 20° C. to about 40° C.,and most preferably about 25° C.

Biotin production is described in U.S. Pat. No. 3,859,167, incorporatedherein by reference.Cis-tetrahydro-2-oxo-4-n-pentyl-thieno[3,4-d]imidazoline is added to aculture medium containing solvent extracted corn meal and otherappropriate identified ingredients in combination with a microbialspecies capable of forming biotin. In general, the microorganism iscultivated for 1 to 10 days, preferably 1 to 8 days, and more preferably2 to 7 days, after which time biotin is separated and purified. In oneembodiment, to purify biotin, cells are removed from the culture medium,the filtrate is absorbed on activated charcoal, and purified with an ionexchange column. Alternative methods of purification are also used suchas crystallization by adjusting the pH of the biotin-contained solutionto near its isoelectric point.

Solvent extracted corn meal can also be further processed to producebiodegradable materials. For instance, the meal of the present inventionmay be incorporated as a thermoplasticising agent. The meal of theinvention may be included in the methods described in U.S. Pat. No.5,320,669, which is incorporated herein by reference. The thermoplasticmaterial is prepared using solvent extracted corn meal, as obtained fromthe process described herein. In one embodiment, the biodegradablethermoplastic composition prepared using the meal of the presentinvention is treated with an organic solvent, and/or optionally across-linking agent, to link together the starch and protein of theextracted corn grain. The cross-linking agent referred to herein may beany compound capable of linking the starch and the protein, such as, forexample, an aldehyde, an acid anhydride or an epoxide. The compositionsso formed using the meal of the present invention can be used to makeextruded or molded articles that are biodegradable, water-resistant,and/or have a high level of physical strength.

Blended products comprising the extracted corn meal of the presentinvention and one or more other oilseed meals are made by one or more ofthe following ways: 1) combining the corn and the other oilseed prior tocracking and/or flaking and subjecting the entire seed mixture to theflaking and extraction process described herein to form a blended meal;2) combining the corn and the other oilseed after cracking andconditioning, but prior to flaking and subjecting the entire seedmixture to an extraction process as described herein to form a blendedmeal; 3) combining the corn and the other oilseed after flaking andsubjecting the entire seed mixture to the extraction process describedherein to form a blended meal; 4) combining the extracted corn meal withextracted or non-extracted other oilseed meal to form a blended meal; or5) combinations thereof to form a blended meal. At any time during theseprocesses, additional components can be added to the blended meals toform a blended product.

The extracted corn meal can also be used in foodstuffs such as snackfood, blended food products, breads, fermentation feedstock, breakfastcereals, thickened food products such canned fruit fillings, puffed orextruded foods, porridge, cardboard and packaging material.

When used in edible products for humans or animals, the extracted cornmeal can be combined with other components such as other meal, otheroilseed meal, grain, other corn, sorghum, wheat, wheat milledbyproducts, barley, tapioca, corn gluten meal, corn gluten feed, bakerybyproduct, full fat rice bran, and rice hull.

The extracted corn meal can also be used as a raw material forproduction of corn protein isolates, for fermentation, or for furtherchemical processing. In addition to enzymes, such as amylases andproteases, can be added to the meal to help facilitate the breakdown ofstarch and proteins.

The extracted corn meal is optionally subjected to conventional methodsof separating the starch and protein components. Such methods include,for example, dry milling, wet milling, high pressure pumping orcryogenic processes. These and other suitable processes are disclosed inWatson, S. A. & P. E. Ramstad, ed. (1987, Corn: Chemistry andTechnology, Ch. 11 and 12, American Association of Cereal Chemist, Inc.,St. Paul, Minn.), the disclosure of which is hereby incorporated byreference. Due to the prior removal of oil from the corn meal, thestarch and protein components of the extracted corn meal are separatedfrom other components more easily than they would be if the corn oilwere not extracted.

Several important quality parameters for the extracted meal include thefat, starch, protein, and moisture content. Methods for evaluatingquality parameters of oilseed meals are disclosed in the AOCS methods,the relevant disclosure of which is hereby incorporated by reference.These methods can also be applied to the extracted corn meal prepared asdescribed herein.

Corn meals derived using different methods or isolated at differenttimes are compared by normalizing the meals to a common moisturecontent. The moisture content of an oilseed protein concentrate, such asa corn meal or whole corn, is determined using AOCS method Ba 2b-82. Thecrude fiber content of corn meal is determined using AOCS method Ba6-84. AOCS method Ba 6-84 is useful for grains, meals, flours, feeds andall fiber bearing material from which the fat can be extracted leaving aworkable residue. The average crude fiber content for the corn meal ofthe invention is 2.0%. Crude protein content of corn meal is determinedusing AOCS method Ba 4e-93 or AOAC 990.03. The starch content of cornmeal is determined using the AACC Method 76-11 (glucoamylase method).This method may be modified with the following changes: weigh 0.1 g ofsample into a culture tube instead of 1 g of sample into an E-flask; andextract free sugar before enzyme digestion.

It is to be understood that the analytical methods provided herein areillustrative examples of useful methods for computing various qualityparameters for the oils and meals described herein. Other suitablemethods are known and may be used to compute the quality parametersdisclosed and claimed herein.

The following examples are included to demonstrate specific embodimentsof the invention. It should be appreciated by those of skill in the artthat the techniques disclosed in the examples which follow representtechniques discovered by the inventors to effectively function in thepractice of the invention, and thus can be considered to constituteexemplary modes for its practice. However, those of skill in the artshould, in light of the present disclosure, appreciate that many changescan be made in the specific embodiments which are disclosed and stillobtain a like or similar result without departing from the spirit andscope of the invention.

EXAMPLE 1 Method for Processing Low Oil Corn

This example describes a continuous solvent extraction process. Thesolvent extraction process consisted fundamentally of four parts:pre-extraction, extraction, meal desolventization, and oildesolventization. These various stages are described in further detailbelow.

Table 1 shows the values for the parameter targets for each of thepre-extraction steps, tempering, cracking, conditioning, and flaking.These parameter targets represent desired values for operation of thedescribed process. The corn type can be produced in a number of waysincluding, but not limited to, using corn such as normal yellow #2 corn,wherein the corn has an oil content of from about 3% by weight to about6% by weight oil; producing grain from a hybrid wherein the grain isbetween about 3% by weight and about 6% by weight oil; or producinggrain from a mixture of plants wherein the grain harvested has acomposite oil level of between about 3% by weight and about 6% byweight.

EXAMPLE TABLE 1 Value Pre-Extraction Variable Corn Type A homogeneous orheterogeneous mixture of corn having a composite oil content of betweenabout 3% by weight and about 6% by weight Throughput (kg/h) 75 TemperingTempered Moisture Content 14 ± 0.5 of Corn Kernel (%) Cracking Crackingroll feed Ambient (˜25° C.) temperature (° C.) Top cracking roll gap Wasdetermined basis 3 mm particle (inches) size ˜ 0.1 Top, slow crackingroll 708 speed (RPM) Top roll speed ratio 1.5 Top roll corrugation RBV -Sharp to sharp Bottom cracking roll gap Was determined basis 3 mmparticle (inches) size ˜ 0.1 Bottom cracking roll speed 708 (RPM) Bottomroll speed ratio 1.5 Bottom roll corrugation RBV - Sharp to sharpConditioning Exit temperature (° C.) 80 ± 5   Exit moisture (%) 14 ± 0.5Capacity (kg.) 100 Indirect (jacket) steam 30-60 (set to maintain exittemperature) (psig.) Flaking Flaker gap setting (inches) ˜0.008 Flakerfeed temperature 75 ± 5 (° C.)

(A) Pre-Extraction

Tempered whole corn was gate fed from a porta-bin to a bucket elevatorto the cracking mill. From the cracking mill, cracks (i.e., particles ofwhole corn) were conveyed to a conditioner, which discharged to aninsulated conveyance system. This system consisted of a second bucketelevator (BE1), air mechanical conveyor, heated steam jacketed conveyor(SJC), and chutes connected in series. From the conveyance system, corncracks were fed to a flaking roll.

Whole corn was tempered to nominally 14.5% moisture by weight by addingwater to “as is” moisture corn in a 350 liter Toronto CoppersmithingToreo Model R-12 ribbon blender. Water was sprayed into the vessel at arate of 2 liters/hr. After the appropriate amount of water was added,the corn was stirred for another hour then allowed to soak for 24 hoursbefore being tested for moisture.

The tempered corn was then cracked using a Roskamp (Waterloo, Iowa)double stand cracking roll. Both top and bottom rolls were set such thatone roll rotated faster than the other. The fast roll on both top andbottom rotated at 1065 revolutions per minute (rpm) with 6 spiral RBVcut corrugations per inch. The slow rolls were cut identically butrotated at 700 rpm. The roll diameters were 9 inches; the roll lengthwas 12 inches. Crack moistures were 13.3 to 15.7%. Cracks of thefollowing average particle size distribution ranges were generated:15.9% retained by US #4 mesh screens, 39.9% retained by US #6 meshscreens, 27.8% retained by US #8 mesh screens, 6.8% retained by US #10mesh screens, 4.3% retained by US #18 mesh screens, and 5.3% passthrough US #18 mesh screens.

The cracked corn particles were conditioned using a steam jacketed screwconveyor manufactured by Scott Equipment Company (New Prague, Minn.),model TB 1814 Tender Blend 18″ screw diameter and 12 feet in length.Three blades swept the perimeter of the inside of the screw. Paddleswere approximately 3 inches wide by 4 inches in length. The screwrotated at 4 rotations per minute. The jacketed side of the conveyor wasfed 30 psig saturated steam. The exit temperature was monitored andadjusted to 80° C.

Flakes were generated from the cracked corn using a Roskamp (Waterloo,Iowa) 2862 flaking mill. The mill used has 62-inch long and 28-inch widerolls. The main drive was designed to turn the fast roll at a nominal300 rpm, and inter-roll drive (IRD) ratio was 8%. Roll pressure was heldconstant at 500 psig. Flaking exit moistures were in the range of 9.1 to11.7%. Exit temperatures were in the range from about 60 to about 83° C.Flake thickness ranged from 0.3 to 0.7 mm. The roll gap was set fromnominally less than 0.025 to 0.30 mm (less than 0.001-0.012 inches)

(B) Extraction

A continuous, nominal 150 kg/hr. Crown (Roseville, Minn.) model II pilotextractor was used to process the flaked corn. This pilot scaleextractor utilized mixed hexanes as a solvent with five(5)counter-current miscella wash zones and a tail wash section.Six-miscella recirculation pumps were utilized. Fresh hexane at 50 to60° C. was fed in the upper portion of the extractor. The dimensions ofthe extractor were 29 feet long, 7.8 inches wide, and 4.5 inches deep.Of the total length, 23 feet were wetted and 19.5 feet of that weresubjected to wash. The actual feed rates varied from about 50 to about120 kg/hr. with a nominal average of about 75 kg/hr. The residence timewas nominally 60 minutes. The solvent-to-meal ratios were adjustedbetween about 0.75:1 and about 1.33:1. Full miscella was sent to the oildesolventization system at about 27 to about 34° C.

Example Table 2 shows the values for the parameter targets for each ofthe extraction steps. These parameter targets represent desired valuesfor operation of the described process.

EXAMPLE TABLE 2 Extraction Variable Value Corn Type A homogeneous orheterogeneous mixture of corn having a composite oil content of betweenabout 3% and about 6% by weight Throughput (kg/h) 75 Extraction Moistureof feed (%) 11-13% Feed temperature (° C.) >50 Residence time (minutes)60 Solvent to meal ratio 1:1 Steam Jacketed Conveyor Dischargetemperature (° C.) Nominally 50 Vacuum (H₂O) 0.2 Desolventization Topdeck temperature (° C.) 100 Bottom deck temperature 70 (° C.) DT vaportemperature (° C.) >70 Sparge steam rate (kg./hr.) Set to achieve DTvapor temperature

(C) Meal Desolventization

Ambient and indirect heat desolventization occurred first in a Schneckensteam jacketed conveyor (SJC). The SJC consisted of a hollow flightscrew inside of a steam jacket. It was 12 feet long and 10 inches indiameter. The open flight screw created a tumbling action as it conveyedthe extracted material through the conveyor. This ensured that allmaterial was exposed to the heated wall. A pneumatic controllerregulated the amount of steam supplied to the jacket. The temperature atthe outlet of the conveyor was monitored and used as the basis for thecontrol of steam supplied to the jacket. Vapors from the conveyor arecollected in the low vacuum condenser by the slight negative pressuredeveloped by the system fan. A double-deck nominal 100 kg-capacitydesolventizer and toaster (DT) with sweep arm agitation was utilized.Dimensions were 36 inches in diameter, 20 inches high per deck. Steamsparge was piped through the top sweep arm only. Meal exit moistureswere in the range of 9.4 to 17.7%. Exit temperatures were in the rangefrom 57 to 104° C.

Hexane recovered from the SJC and extractor was condensed, dewatered,and recycled to the extractor.

(D) Oil Desolventization

Oil desolventization was executed using a Rising film evaporator. Thisunit consisted of sixteen 1.5 cm diameter tubes inside a large jacket.The jacket was filled with steam, which heated the tubes. Theextract-laden liquid (normally oil in hexane called miscella) was pumpedinto the bottom of the tubes. As it traveled up the inside of the tubes,steam heat caused the liquid to boil. The vapors held the liquid againstthe wall of the tube in a thin, rising film. At the top the liquid andvapor were allowed to separate. The oil flowed into an overflow pipe tothe oil stripper, while the vapors were carried over to a condenser. Thetubes were under vacuum so that the liquid boiled at a low temperature.

The oil stripper was a disc-and-donut style distillation column. Theliquid was spread out in a thin film over a disc, drips down onto adonut and returns back onto a disc. Thus, the oil cascaded down thecolumn. At the same time, steam was injected into the bottom of thestripper. This steam passed over the liquid film removing the solventremaining in the liquid. A steam jacket to keep the liquid and steam hotsurrounded the disc and donut column. The oil stripper was also undervacuum and the vapors (solvent and steam) went to the same condenser asthe RFE vapors. The stripping steam went through a demister to removewater droplets before going into the oil stripper.

Hexane recovered from the rising film evaporator and the oil stripperwere condensed, dewatered, and recycled to the extractor.

EXAMPLE 2 A Method of Recovering Lighter Particles Generated During aContinuous Solvent Extraction Process for Separating Oil from CornHaving an Oil Content Between 3% and 6%

This example sets forth one method of recovering lighter particles, suchas fines, generated during a moisture removal step from corn processedin a manner illustrated in Example 1.

Corn is processed as described in Example 1 (Cracked and flaked orcracked). The product from the whole flaked corn from the flakingprocess is heated to remove moisture using standard processing equipmentsuch as a Kice (Wichita, Kans.) classifier model A2612. During thismoisture removal step an air stream is provided where the velocity ofthe air stream is controlled. The velocity of the air stream isregulated such that the smaller and lighter particles are carried awayin the air stream, hence separating them from the heavier flakes. Thelighter particles are then recovered by standard process equipment suchas a baghouse. The recovered lighter particles are then introduced intostarch-containing product streams for the recovery of starch or areadded to the meal stream after solvent has been removed from the meal.

EXAMPLE 3 A Method of Recovering Lighter Particles Generated During theCracking Step of a Continuous Solvent Extraction Process for SeparatingOil from Corn Having an Oil Content Between 3% and 6%

This example sets forth one method of recovering lighter particles, suchas fines, generated during the cracking step from corn processed in amanner illustrated in Example 1.

Whole corn kernels are cracked using a standard cracking mill rollersuch as Roskamp™ (Waterloo, Iowa) model number 6.5. During this crackingstep an air stream is provided whereas the velocity of the air stream iscontrolled. The velocity of the air stream is regulated such that thesmaller and lighter particles a re carried away in the air stream, henceseparating them from the heavier cracks. The lighter particles are thenrecovered by standard process equipment such as a baghouse. Therecovered lighter particles are then introduced into starch-containingproduct streams for the recovery of starch.

EXAMPLE 4 A Method of Recovering Lighter Particles Generated Before andAfter the Flaking Process by Means of a Liquid Spray During a ContinuousSolvent Extraction Process for Separating Oil from Corn Having an OilContent Between 3% and 8%

This example sets forth the recovery by means of a liquid spray of finesgenerated before and after the flaking process from corn processed in amanner illustrated in Example 1. The liquid spray can be a substancethat adds value to the resulting meal as well as recovers the value fromthe fines.

Corn is processed as described in Example 1. The pre-flaking crackedcorn and the post-flaking corn flakes are sprayed or misted with wateror oil that physically eliminates the lighter, airborne particles. Thewater source can be pure water, process water, water or oil that hasbeen supplemented with nutritional additives such as vitamins, enzymesor minerals. The oil can be corn oil. The water or oil stream containingthe particulates is carried away from the heavier particles in each caseand is collected. The particulates are separated from the liquid usingstandard process equipment such as through centrifugation. The recoveredlighter particles are then introduced into starch-containing productstreams for the recovery of starch.

All references, including publications, patent applications, andpatents, cited herein are hereby incorporated by reference to the sameextent as if each reference were individually and specifically indicatedto be incorporated by reference and were set forth in its entiretyherein.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. Recitation of ranges of values herein are merely intended toserve as a shorthand method of referring individually to each separatevalue falling within the range, unless otherwise indicated herein, andeach separate value is incorporated into the specification as if it wereindividually recited herein. All methods described herein can beperformed in any suitable order unless otherwise indicated herein orotherwise clearly contradicted by context. The use of any and allexamples, or exemplary language (e.g., “such as”) provided herein, isintended merely to better illuminate the invention and does not pose alimitation on the scope of the invention unless otherwise claimed. Nolanguage in the specification should be construed as indicating anynon-claimed element as essential to the practice of the invention.

Preferred embodiments of this invention are described herein, includingthe best mode known to the inventors for carrying out the invention. Ofcourse, variations of those preferred embodiments will become apparentto those of ordinary skill in the art upon reading the foregoingdescription. The inventors expect skilled artisans to employ suchvariations as appropriate, and the inventors intend the invention to bepracticed otherwise than as specifically described herein. Accordingly,this invention includes all modifications and equivalents of the subjectmatter recited in the claims appended hereto as permitted by applicablelaw. Moreover, any combination of the above-described elements in allpossible variations thereof is encompassed by the invention unlessotherwise indicated herein or otherwise clearly contradicted by context.

We claim:
 1. A corn meal remaining after the extraction of oil fromwhole corn.
 2. The corn meal of claim 1, wherein the whole corn has anoil content of from about 3% to about 6%.
 3. The corn meal of claim 2,wherein the whole corn is tempered prior to extraction of the oil. 4.The corn meal according to claim 3, wherein the tempered corn is crackedprior to extraction of the oil.
 5. The corn meal according to claim 4,wherein the cracked corn is conditioned prior to extraction of the oil.6. The corn meal according to claim 5, wherein the conditioned corn isflaked prior to extraction of the oil.
 7. A method of processing wholecorn comprising: 1) tempering the whole corn; 2) cracking the temperedcorn; 3) conditioning the cracked corn; and 4) flaking the conditionedcorn.
 8. The method according to claim 7, wherein the whole corn has anoil content of from about 3% to about 6%.
 9. The method of claim 8,further comprising the step of extracting the flaked corn to producecorn meal and corn oil.
 10. A method of recovering lighter particlesgenerated during the processing of corn comprising separating lighterparticles from heavier particles by passing a stream of gas over thecorn such that lighter particles are carried away in the gas stream. 11.The method of claim 10, wherein the gas is selected from the groupconsisting of air, nitrogen and argon.
 12. A method of recoveringlighter particles generated during the processing of corn comprisingseparating lighter particles from heavier particles by passing a liquidspray over the corn such that the lighter particles are carried away.13. The method of claim 12 wherein the liquid spray is water.
 14. Themethod of claim 13, wherein the liquid spray further comprises at leastone component selected from the group consisting of vitamins, minerals,enzymes and combinations thereof.
 15. The method of claim 14, whereinthe liquid spray further comprises a caustic liquid.